Plant growth inhibition with n aryl pyrid 2 ones

ABSTRACT

A METHOD OF REGULATING PLANT GROWTH WITH COMPOUNDS BELONGING TO THE CLASS OF N-ARYL PYRID-2-ONE 4,6-DIALKYL (AND 4,5,6-TRISUBSTITUTED)-3-CARBOXYLIC ACIDS AND THEIR ACID HALIDES , AMIDES, ESTERS AND PHYSIOLOGICALLY ACCEPTABLE SALTS. THIS INCLUDES INHIBITION OF PLANT GROWTH, CONTROL OF FLOWERING AND FRUITING, AND HYDBRIDIZATION.

nited States Patent Ofice 3,761,240 PLANT GROWTH INHIBITION WITH N-ARYL-PYRlD-Z-ONES Michael C. Seidel, Levittown, Kenneth L. Viste, Warminster, and Roy Y. Yih, Doylestown, Pa., assignors to Rohm and Haas Company, Philadelphia, Pa.

No Drawing. Continuation-impart of application Ser. No.

7,256, Jan. 30, 1970, which is a continuation of abandoned application Ser. No. 779,198, Nov. 26, 1968, which in turn is a continuation-in-part of application Ser. No. 698,106, Jan. 16, 1968, now Patent No. 3,503,986. This application Feb. 10, 1971, Ser. No.

Int. Cl. A01n 9/22 U.S. CI. 71-76 14 Claims ABSTRACT OF THE DISCLOSURE A method of regulating plant growth with compounds belonging to the class of N-aryl pyrid-2-one 4,6-dialkyl (and 4,5 ,6trisubstituted)-3-carboxylic acids and their acid halides, amides, esters and physiologically acceptable salts. This includes inhibition of plant growth, control of flowering and fruiting, and hybridization.

This application is a continuation-in-part of our copending application U.S. Ser. No. 7,256, filed Jan. 30, 1970, now U.S. Pat. 3,576,814, which in turn is a continuing application of U.S. Ser. No. 779,198, filed Nov. 26, 1968, now abandoned, which in turn is a continuationin-part of U.S. Ser. No. 698,106, filed Jan. 16, 1968, now U.S. Pat. No. 3,503,986.

This invention is concerned with new organic compounds belonging to the general class of N-aryl pyrid-2- ones. It also relates to the biological activity of these structures. In particular they are useful for influencing the growth and development of plants in various ways as will be more fully developed hereinafter.

These new structures may be depicted by the formula:

1 Rs I {II-Y Ra N aryl wherein R and R are methyl or ethyl, R is hydrogen, methyl, ethyl or chlorine, Y is selected from the group consisting of Br, Cl, NH;,, and OR wherein R is hydrogen, alkyl groups of 1 to 5 carbon atoms or a physiologically acceptable salt-forming cation.

Aryl is selected from the group consisting of X is selected from the group consisting of amino, fluoro,

chloro, bromo, iodo, alkyl of 1 to 5 carbon atoms, trifluoromethyl, methoxy and nitro,

X' is selected from the group consisting of fiuoro, chloro,

bromo, iodo, methyl, trifluoromethyl and methoxy,

nis0,1or2and X in Patented Sept. 25, 1973 may be hydrogen when n is 1 or 2 and X is at least one halogen in the 3-position.

The most closely related compound to these known in the literature is 1-phenyl-4,6-dimethylpyrid-2-one-3-carboxarnide. This was prepared by W. Reid et al. as described in Annalen 626, (1959). The method used was the condensation of cyanoacetanilide with acetylacetone to produce 1-phenyl-4,6-dimethyl-3-cyanopyrid-2-one which was then hydrolyzed to the corresponding 3-carboxamide.

Typical compounds within the scope of this invention include:

1- 3-fluorophenyD-3 -carboxy-4,6-dimethylpyrid-2-one l- (3 -chlorophenyl) -3 -carboxy-4,6-dimethylpyrid-2-one 1- (3 -bromophenyl) -3 -carboxy-4,6-dimethylpyrid-2-one 1- 3 -iodophenyl) -3-carb oxy-4,6-dimethylpyrid-Z-one 1- (4 aminophenyl) -3 -carboxy-4,6-dimethylpyrid-2-one 1- (4-fluoropheny1) -3 -carboxy-4, 6-dirnethylpyrid-2-one 1- (4-chlorophenyl) -3-carboXy-4, G-dimethylpyrid-Z-one 1- (4-bromophenyl) -3-carboxy-4,6-dimethylpyrid-2-one 1- (4-iodophenyl) -3-carboxy-4,6-dimethylpyrid-2-one 1- (4-methylphenyl) -3 -carb oxy-4,6-dimethylpyrid-2-one 1- (4-methoxyphenyl) -3 -carb oxy-4,6-dimethylpyrid-Z-one 1- (2,4-dichlorophenyl) -3-carboxy-4,6-dimethylpyrid-2- one 1- 2,4-dibromophenyl) -3-carboxy-4,6dimethylpyrid-Z- one 1-(2-methy1-4-chlorophenyl)-3-carboxy-4,6-dimethylpyrid-Z-one l-( 2-chloro-4-methylphenyl -3-carboxy-4,6-dimethylpyrid-2-one 1- (2-methoxy-4-bromophenyl) -3 -carb oxy-4,6-dimethylpyrid-Z-one 1- (2-fluoro-4-chlorophenyl) -3 -carboxy-4,6-dimethylpyrid-Z-one 1- (3 -fluoro-4-chlorophenyl)-3-carboxy-4,6-dimethylpyrid-Z-one 1- 3 ,4 dichlorophenyl) -3-carb oxy-4,6-dimethylpyrid-2- one 1- (3-chloro-4-bromophenyl) -3 -carboxy-4,6-dimethylpyrid-Z-one 1- 3 -chloro-4-methylphenyl) -3-carb oxy-4,6-dimethylpyrid-2-one 1- (4-ch1oro-3-methylphenyl) -3 carb oxy-4,6- dimethylpyrid-2one 1- (3 -methyl-4-methoxyphenyl) -3 -carb oxy-4,6-dimethylpyrid-Z-one 1- (3 ,4-dimethylphenyl) -3 -carb oxy-4,6-dimethylpyrid- 1- 3 -chloro-4-methoxyphenyl) -3-carboxy-4,6-dimethylpyrid-2-one l- (3 -chloro-4-nitrophenyl )-3 -carboxy-4,6-dimethylpyrid- 2-one 1- (2,3 ,4-trich1orophenyl)-3 -carboXy-4,6-dimethylpyrid-2- one 1- (2,4,6-trichlorophenyl) -3-carboxy-4,6-dimethylpyrid- 2- one 1- (2-methyl-3 ,4 dichlorophenyl -3 -carboxy-4,6-dimethylpyrid-2-one 1- (4-methyl-2,3-dichlorophenyl) -3 -carb oxy-4,6-dimethylpyrid-Z-one 1- 4-methyl-2-chloro-6-fluorophenyl -3-carb oxy-4,6-dimethylpyrid-2-one 1- (4-fluoronaphthyl -3-carboxy-4,6-dimethylpyrid-2-one 1- 4-methynaphthyl) -3 -carb oxy-4,6-dimethylpyrid-2rone 1- (4-trifluoromethylnaphthyl) -3 -carboxy-4,6-dimethylpyrid-Z-one 1- (4-methoxynaphthyD-3 -carboxy-4,6-dimethylpyrid-Z- one and salts of the above 1- 3-iodophenyl) -3-carbamyl-4,6-dimethylpyrid-2-one 1- (4-methylphenyl) -3-carbamyl-4,6-dimethylpyrid-2-one 1- (4-methoxyphenyl -3 -carbamyl-4,6-dimethylpyrid-2- one l- (4-bromophenyl) -3-carb amyl-4,6-dimethylpyrid-Z-one l-(4-chlorophenyl) -3 -carbamyl-4,6-dimethylpyrid-2-one l- (2,4-dichlorophenyl -3-carbamyl-4,6-dimetyhlpyrid-2- one l- 2,4-dimethylphenyl) -3-carbamyl-4,6-dimethylpyrid-2- one 1-(2-bromo-4-methylphenyl) -3-carbamyl-4,6-dimethylpyrid-2-one 1- 2-bromo-4-fluorophenyl-3-carbamyl-4,6-dimethylpyrid-2-one l- (3-methyl-4-fiuorophenyl) -3 -carbamyl-4,6-dimethylpyrid-Z-one 1- (3 ,4-dichlorophenyl -3-carbamyl-4,6-dimethylpyrid- 2-one 1- (3 ,4-dimethylphenyl -3-carb amyl-4,6-dimethylpyrid-2- one 1-(3 ,4-dimethoxyphenyl) -3 -carbamyl-4,6-dimethylpyrid- 2-one l- 3 ,4-dibromophenyl) -3-carbamy1-4,6-dimethylprid-2- one 1- (3 ,4-difiuorophenyl -3-carbamyl-4,6-dimethylpyrid-2- one 1- 3-chloro-4-methoxypheny1) -3-carbamyl-4,6-dimethylpyrid-Z-one 1- 3 -methyl-4-bromophenyl) -3-carbamyl-4,6-dimethylpyrid-2-one 1- (2,4,6-trichlorophenyl)-3 -carbamyl-4,6-dimethylpyrid- 2-one 1- (2,3 ,4-trichlorophenyl) -3-carbamyl-4,6-dimethylpyrid- Z-one 1- (3 ,4-dichlorophenyl -3 -methoxycarbonyl-4,6-dimethylpyrid-Z-one 1-(4-chlorophenyl -3-ethoxycarbonyl-4,6-dimethylpyrid- 2-one Based on a plant growth regulatory activity, preferred compounds of this invention include 1(4-chlorophenyl)- 3-carboxy-4,6-dimethylpyrid-2 one 1 (3,4 dichlorophenyl)-3-carboxy-4,6-dimethylpyrid 2 one and their water-soluble salts.

Water soluble salts of the compounds of this invention where Y of Formula I is OH include the alkali metal salts, preferably the sodium and potassium; the ammonium; mono, di and trialkylammonium wherein each alkyl group may contain up to 4 carbon atoms, preferably methylammonium, dimethylammonium, trimethylammonium and triethylammonium; ethanolamine and propanolamine salts such as the 2-hydroxyethylammonium, Z-hydroxypropylammonium, bis(2 hydroxyethyl)ammonium and tris(Z-hydroxyethyl)ammonium; and quaternary ammonium salts such as tetramethylammonium and chlorine. Other useful salts include the alkaline earth salts, particularly the calcium and magnesium, alumisalts, particularly the calcium and magnesium, aluminum, cadmium, copper, ferric, ferrous, manganese, nickel and zinc.

The compounds of this invention may be prepared by hydrolysis of 1-aryl-3-cyano-pyrid-2-ones corresponding to the formula:

R5 l ON Aryl (II) wherein R R R and aryl have the above meanings. Partial hydrolysis of the C 3N group to -CONH results in the 1-aryl-3-carbamyl-pyrid-2-ones. In many instances hydrolysis results in a mixture of the 3-carbamyl and 3-carboxy derivatives and these may be separated by conventional means such as by converting the 3-carboxy derivative to a water-soluble salt and removing the insoluble 3-carbamyl derivative. The reaction mixture consisting essentially of the two types of hydrolysis products with generally a minor amount of the unreacted cyano precursor can be used for biological purposes directly without separation. Tests on the cyano precursor have shown that it neither has biological activity nor does it interfere with the biological activity of the hydrolysis products.

The 1-aryl-3-cyano-pyrid-2-ones (Formula II) may be prepared by condensation of beta-diketones with N-aryl cyanoacetamides of the formula:

NCCH CONH-Aryl (III) in the presence of a basic catalyst. The reaction may be depicted as follows, using the mono-enol form of the beta-diketone Formula II This is usually a facile reaction in the temperature range of ISO-250 C. The end of the reaction is judged when the removal of ethanol is essentially completed. The reaction product may be purified by standard means, such as recrystallization, or may be used Without further purification. Refer to Piccinini et al., Chemishes Zentralblatt 78, 335 (1907).

In the condensation of beta-diketone with the N-aryl acetamide equimolar amounts of the two reactants are normally used, although excesses of either reagent are permissible. In some instances, it may be expedient to use an excess of the beta-diketone.

The condensation of the beta-diketone with an N-aryl cyanoacetamide is preferably carried out in the presence of a solvent. Suitable solvent include alcohols, ethers, aliphatic hydrocarbons, aromatic hydrocarbons, dimethylformamide, dimethyl sulfoxide and carbon tetrachloride. The preferred solvents are the alcohols such as methanol, ethanol, isopropanol and monoethers of ethylene glycol. Heat is required for the condensation and this is usually obtained at the reflux temperature of the solvent used. Temperatures in the range of 50 to C. are suitable.

The condensation of the beta-diketone with an N-aryl cyanoacetamide is catalyzed by basic catalysts. Typical catalysts include inorganic bases, amines and quaternary ammonium hydroxides. Amine catalysts are preferred and good results have been obtained with piperidine, pyridine, diethylamine and triethylamine for example. General conditions for this type of condensation are reviewed in Heterocyclic Compounds, edited by A. Weissberger, Interscience Publishers, 1962, in Part III on Pyridinols and Pyridones, pages 525-531.

The 1-aryl-3-cyano-pyrid-2-ones can also be prepared by the general method described in the above cited book Heterocyclic Compounds on page 596. This consists of quaternizing a 3-cyano-pyridine with an iodobengene or naphthalene of the structure (X )n or k in a solvent having a high dielectric constant, such as acetonitrile, and oxidizing the resulting pyridinium salt with alkaline potassium ferricyanide to the correspond ing u-pyridone. The reaction may be depicted as follows:

Rs CN (11'). I

ryl (IV) K3F6(CN)0, alkali Formula IV Formula II The 1-aryl-3-cyano-4,6-dimethylpyrid-2-ones may also be prepared by a ring-closure procedure generally described in the above cited book Heterocyclic Compounds at pages 540-541. By this procedure acetone is condensed with a p-ketoamide of the type m oooon, CHEOH R5 000cm HaN-Aryl R 0 R0 0 Aryl (V) The compounds of Formula V may be converted to the corresponding carboxy compounds or their water-soluble salts by standard hydrolytic procedures. 7 The hydrolysis of 1-aryl-3-cyano-pyrid-2-ones may be exemplified by the following reaction sequence:

liryl Aryl (II) (VI) (VII) The hydrolysis of the nitrile (Formula [I) proceeds to either the amide (Formula VI) or the acid (Formula @VII) under acidic conditions. Aqueous organic and min-' eral acids are suitable for this purpose. Typical of such acids are formic, acetic, hydrochloric, sulfuric and phos- -=.phoric. The temperature requirements for the hydrolysis are such that the temperature must be high enough to .allow the hydrolysis to proceed but not sufficiently high .to cause decarboxylation. This is normally in the range of 50 to 150 C., with a preferred range of 80 to 120 C. The cyano compounds of Formula II can be converted "to the carbamyl derivatives of Formula VI by hydrolysis with hydrogen peroxide in dilute base or by other methods known in the art. The carbamyl derivatives can be hydrolyzed to the free acids of Formula VH by means of nitrous acid or by other hydrolytic procedures well known in the chemical art.

The acids of Formula VII are readily converted to derivatives. For example, direct esterification with alco- "hols gives esters and reaction with halogenating agents suclras oxalyl chloride, thionyl chloride or bromideand phosphorus pentachloride gives the acid halides. The acid halides can in turn be converted to esters, amides, anilides and other common derivatives by standard procedures.

The following examples are illustrative of preparations of the compounds of the invention, but are not to be construed as limitations thereof. The example numbers correspond to those given in subsequent Tables III, IV, V, VI and VII.

EXAMPLE 2 Preparation of 1- (4-chlorophenyl)-3-carboxy- 4,6-dimethylpyrid-2-one (a) 1-(4-chlorophenyl)-3-cyano 4,6 dimethylpyrid- 2-one.A reaction mixture consisting of 19.4 g. (0.1 mole) of p-chlorophenylcyanoacetanilide, 10 g. (0.1 mole) of pentane-2,4-dione, 5 ml. of piperidine and 200 cc. of ethanol was refluxed for 3 hours. The reaction mixture was cooled to give a solid which was filtered off, washed with methanol and recrystallized from glacial acetic acid to give 22 g. of crystals. This white solid melted at 314-316 C. It was found by analysis to contain 64.96% C, 4.25% H and 10.76% N; calculated for C H ClN O (molecular weight, 258.7) is 64.99% C, 4.29% H and 10.83% N. It is an 83% yield of 1-(4- chlorophenyl)-3-cyano-4,6-dimethylpyrid-2-one.

(b) 1-(4 chlorophenyl)-3-carboxy-4,6-dimethylpyrid- 2-one.--Forty grams (0.155 mole) of 1-(4-chlorophenyl)- 3-cyano-4,6-dimethylpyrid-2-one was dissolved ina solution of 100 ml. of concentrated sulfuric acid in 60 ml. of water. The reaction mixture was heated on a steam bath overnight. After cooling the product was poured into water to give a solid which was filtered off and recrystallized from ethanol. The isolated solid was 22.5 g. of white solid which melted at 215-217" C. This was found to contain by analysis 60.60% C, 4.27% H and 5.10% N; calculated for C H ClNO (molecular weight, 277.7) is 60.55% C, 4.36% H and 5.05% N. The product is a 52% yield of 1-(4-chlorophenyl)-3-carboxy-4, 6-dimethylpyrid-Z-one.

EXAMPLE 19 Preparation of 1-(4-chlorophenyl)-3-carbamyl- 4,6-dimethylpyrid-2-one A reaction mixture consisting of 777 g. (3 moles) of 1-(4 chlorophenyl)-3-cyano-4,6-dimethylpyrid 2 one, 1940 ml. of concentrated sulfuric acid and 1164 ml. of water was heated on a steam bath at 95 C. for 15. hours. The cooled mixture was poured into 7 1. of water and the resulting solid was filtered off. The solid was treated with 1600 g. of 25% aqueous sodium hydroxide, filtered and the solid residue treated with 2200 g. of 10% aqueous sodium hydroxide with stirring for 4 hours at room temperature. The product was filtered and from the filtrate there was isolated 326 g. (a 39% yield) of 1- (4-chlorophenyl)-3-carboxy-4,6-dimethylpyrid-2-one. The insoluble residue, which was 257 g. of solid melting at 206-212? C., was washed with 1000 g. of 10% aqueous sodium hydroxide, then with water, filtered and the residue dried to give 250 g. of almost white solid, melting at 211- 213 C. By NMR this was shown to be essentially 1-(4- chlorophenyl)-3-carbamyl-4,6-dimethylpyrid-2-one and as such is a 30% yield. A sample of the solid was recrystallized from a 50:50 mixture of acetone-methanol to give the product as a white crystalline solid melting at 222- 226 C. This solid was found to contain by analysis 61.71% C, 4.76% H, 12.65% Cl, 10.01% N and 11.39% 0; calculated for C H ClN O (molecular weight, 276.7) 60.76% C, 4.73% H, 12.82% Cl, 10.13% N and 11.56% 0.

EXAMPLE 32 Preparation of the'sodium salt of 1-(3,4-dichlorophenyl) -3 -carboxy-4,6-dimethylpyrid-2-one To a solution of 177.5 g. of 50.2% aqueous sodium hydroxide (2.2 moles) in 3800 g. of deionized water 7 was added 722 g. of 96% 1-(3,4-dichlorophenyl)-3-carboxy-4,6-dimethylpyrid-2-one (2.22 moles). This was stirred until solution resulted. The solution was poured onto trays and the water allowed to evaporate to give a solid which was then dried in a forced-draft oven at about 50 C. for 4 hours. There was obtained 872 g. of a dry tan-colored powder which melted with decomposition at 244 C. Analysis showed it to contain 17.5% water. Mass spectrographic analysis indicated homogeneity. The product was recrystallized from water. Titrafirmed that the product was exclusively an ester. The solid was found to contain by analysis 61.7% C, 4.70% H, 12.58% Cl, 4.70% N and 16.44% calculated for C H ClNO is 61.75% C, 4.84% H, 12.17% Cl, 4.80% N and 16.44% 0. The product is a 76% yield of 1-(4- chlorophenyl) 3 methoxycarbonyl-4,6-dimethylpyrid- 2-one.

TABLE I.-PREPARATION OF N -Aryl eyanoaeetnmldos,

NCGHzC(O)NH-Aryl tion with 0.5 N hydrochloric acld showed it to be 96% Melting pure. It melted at 253-255 C. The product is a quantita- (Point tive yield of the sodium salt of 1-(3,4-dichlorophenyl)-3- Pmpammn carboxy-4,6-dimethylpyrid-2-one. 4tbromo-2-cyanoacetaniillide 198-200 s q salt of 0 p y1)-3- ar y-4,6- 15 ig gfg gjggggggggg fgg fgi fgg dimethyl r1d-2-one Example 30) was prepared in the gam -2 annar'nfnnilidn 207-209 Py 4' 9th 12 n'nman 'r n'llidn 1351 7 -m n a same way. The recrystallized solid was found to be 95.7% 4,mflugromhybhyanoacetamhde 190492 pure by titration and melted at 270-272 C. 4'-isopropyl-2-cyannamtanilida 170.172 4rnethoxy-2-cyan0aeetanilide 134-135 EXAMPLE 35 gzntro-2-gy t ll irliirzl Preparation of 1-(4-chlorophenyl)-3-methoxycarbonyl- 3:clllllgrr%-2-csglrlgiiitiniliflz 131-134 2'4,'-dicl1l0r0-2- ym|nm-ntnnilirin 11 23 4,6-d1methy1pyr1d-2-one 3',4'.di h1om-2- yannnmfnnilirla 161-164 3-fluoro-4-methyl-2-cyanoaeetanil1de 178-180 A reaction mnrture consisting of 10 g. (0.036 mole) g hlgkrloiti uifihyl-g-cyanoacegagiilfigeu I 1118 y '0 01'0- -eyanoace a 0 of (4 chlorophenyl) 3 carboxy dlmethyl 3-trltluoromethyl-i-chloro-2-cyanoacetanilide... 131-133 yr1d-2-one, 100 ml. of methanol and 1 ml. of concen- 25 {AI-dimethyl-Z-cyanoacetaniiide 138-140 trated hydrochloric acid was stirred at reflux temperature 2, 1, g,1:ggfigg g gggfiggggzgg ggg-- 533 5 for about 16 hours. It was cooled to 10 C. to give a white 2' diioro-fiAdichloro-kyanoaeetaniiide. 183-185 solid which was filtered off, washed with cold methanol $538 and dried. The product was 8 g. of a light tan crystalline N -(4-ch1oronaphthyl)-2-cyanoacetanilld 219-280 solid melting at 188-189 C. Infrared spectroscopy con- TABLE II CN Preparations of 1aryi-3-cyano-4,6-dimethylpyrid-2-ones, I

OH -O i Aryl Analysis Melting oint; Empirical Ele- Calcu- Preparation C.) formula merit Found lated 1-(4-b1-omoph0ny1)3-cyano-4,6-dimothy1pyrld-2-0ne 300 CuHnBrNzO 0 55. 25 $2 a 2 :2 22 o 5172 512a 1.(4. h1 gopheny1)-3-cyano-4,6-dimethylyprid-2-One.41:: 314-316 CuHnCINaO 1-(i-fluorophenyi)-3-cysno-4,6-dimethylpyrld-2-0ne..: 272-274 C11H11FN1O .2% 62%;: F 1105 11 as N 11.27 11.57

1-(4-i0dopi1onyi)-3-eyeno-4,6-dimethylpyrid-2-0ne... 300 CnHuINzO g: i: 9&1 2 o 4102 4157 1-(4-metl1ylphenyl)-3-cyano-4,6-dimethylpyrid-2-one...::::.;::;:;;.: 274-276 CufluNso 72. 763.3% N 11111 11115 O 7.21 6. 73

1-(-trifluoromethyiphenyl)-3-cyano-4,6-dimethylpryld-2-one....;;...; -182 01111 11 11010 6 1 .32 6%.92 N Ma 9158 F 18. 96 19. 51

1-(4-isopropylphony1)-3-cyano-4,6-dimethyipyrid-2-one 261-263 C11HiiN|0 7%.33 73.3 N 10130 10151 O 6.17 6.02

1-(4-methoxyphenyl)-3-cyano-4,6-dimethy1pyrld-2-one.;;:.:.;-'....-:.: 247-240 CiiHuNa a g 721.22 7g.gg N 11I15 11102 0 12.77 12.58

1-( i-nitrophenyl)-3-oyano4,0-dlmethylpyrid-2-ono ...-:1: 278-281 CuHnN os g: N 15101 15153 O 17.59 17.84

1-t8-flnprophenyD-3-cyano-4,-dignethylpyrid-2-one. :7 287-289 Cu nFNfl H 2-9: 112- 43 N 11170 .1151

TABLE IV CONE: Examples ot1-aryl-3-carbamyl 1-4,6-dimethy1pyrid-2 ones CH; N

I Z I x! Analysis Melting mm wmmm mwnww amen mama wean wanna mwwmn mmmmm m mm mama mm m n m ma am a m a um w nd e 1 76mm u 4 0 a menu women mama mama ma mmmnm mmmwm manna mmm mwmm m a when m ma m ma a and nd m n m e5 1 7 1 F e m n l 1 F m McnFN cnrno onNo onNo onaN ncNo onmNo enmNo on N enNo n S 2 4 IE 2 0 .1 an F 0 i 0. a 0 0 a N w M m m a N m N N m IN N 2 8 N m I 1 F We S0. mm "Wm T... N. a u u I. ED m an a a. a a. m m m. m mm Em m0 0. 0 G. G. C C G C 0 MW 0 1 L mm m. m m a m m a w. my me vi. a a H m 9+ a. m W mm %m 2 H m m 2 1 FE 3 E H H L t I F U m flu m. 0 PW... x nn H n n a a z a a a m m X0 m an m m m x 1 m m n H m o c e m n u u n u u a n n m e m e n a u n n u n n D A m n n n u u I T v n n u u u w X Em a a a a. a 2 z a E The compounds of this invention have been found to produce a variety of plant responses. These responses are observed when the compounds alone or in a carrier or as formulations are applied to the plant itself, as by foliar application, or to plant parts such as by seed treatment or to the environment or habitat of the plant, such as by soil drenching or soil incorporation. The most outstanding p1ant-growth influencing property is suppression of growth. This is most commonly found to be a growth inhibitory action on the stem, i.e., stem elongation is inhibited. in other instances flowering or seed formation is altered. In other cases malformation of leaves is noted. Sometimes particularly at high dosages, a plant species may be herbicidally sensitive.

2-one.

31. Cupric salt of 1-(4-ehlorophenyl)-3-carboxy-4,6-dimethylpyrid- Z-one (melting point 205-210 C decomposition).

32. Sodiurg galt oi 1-(3,4-d1eh1orophenyl)-3-carboxy-4,6-dimethylpyn -one.

33. Dimethylamine salt of 1-(4'chlorophenyl)-3-earboxy-4,6-

dimethylpyrid-Z-one.

ylamine salt of 1-(3,4-diehlorophenyl)-3-carboxy-4,6- dimethylpyn'd-Z-one.

lg-3-methoxycarbonyl-4 6-dimethy1pyrid-2-one.

36. 1-(4-ch1orophenyl -3-isopropoxycarbonyl-4,6-d1methylpyrid-2- one (melting point, 133 0.).

37...... 1-(4-chlorophenyl)-3-ehloroformy1-4,6-dimethylpyrld-2-one (melting point, Bil-135 0.).

30...- Sodium salt of 1-(4-chlorophenyl)-3-earboxy-4,6 dimethy1py1id- 34, Dlmeth 35 l-(i-ehloropheny TABLE VII-Continued Analysis Melting point Empirical Ele- Calcu- Ex. R R R Y C.) formula ment Found late 48 02115 H (32H: OH 126-127 CiuHuClNOa C 62.92 62. 85 H 5.41 5.27 Cl 11.61 11.60 N 4.81 4.58 0 15.54 15.70

49 CH; 01 CH: OH 176-178 CuHnClzNOs C 53.89 53.84 H 3. 54 3.55 01 22.60 22.75

Preemergence herbicidal activity has also been obtained. Individual plant species give dilferent types of responses and any one or several of these plant responses may be observed for any given species. The major contribution of the compounds of this invention to the field of plant growth regulation is that they provide non-injurious plant growth regulants which inhibit stem elongation of many weed, crop and woody species and alter flowering and fruit development.

-A soil drench test was used as one method for evaluating the plant growth regulating properties of the compounds of this invention. .In this test, seeds or plants were planted in pots and at a given stage of growth the soil was watered with a preparation containing the compound at given dosages in terms of pounds per acre. Growth responses were subsequently observed.

In one such test about 20 wheat seeds were planted in a 4-inch pot and allowed to grow for 11 days, at which time the second leaf of wheat was emerging. A solution or suspension of the chemical was prepared by dissolving the compound in about 1 ml. of acetone or water and adding suflicient water to make 50 ml. The amount of chemical was such as to provide 2 and 20 pounds per acre. For example 2 mg. give 2 lbs./ a. or 2.2 kilos per hectare. Each test was run in triplicate and untreated plants were included as controls. Four weeks after treatment the overall height of the plants from the soil level to the leaf tip was measured. The percent inhibition was calculated as height of treated plant height of control plant The following Table VIII gives the results.

Percent inhibition= 100 100 X Percent inhibition at- Percent inhibition at Example 2 lbs./a. 20 lbs/a. Example 2 lbs./a. 20 1bs./a.

a Data approximately two weeks after treatment.

In this type of test the following compounds gave no inhibition of wheat plants, i.e. the plants were similar to untreated controls. 1-phenyl-3-carboxy-4,6-dimethylpyrid-2-one 1-phenyl-3-carbamyl-4,6-dimethylpyrid-2-one 1- (2-chlorophenyl) -3-carboxy-4,6-dimethylpyrid-2-one 1- 4chlorophenyl) -3-cyano-4,6-dimethylpyrid-2-one 1- (3 ,4-dichlorophenyl) -3 -cyano-4,6-dimethylpyrid-2-one For foliage spray tests, the compounds were dissolved in an appropriate solvent, usually acetone for the amides, acides and esters and water for the salts and sprayed onto the foliage at a given dosage per acre in a carrier volume of about 50 gallons per acre. Growth responses were subsequently observed. In one such test the compounds of Examples 2, 30 and 33 were compared, using elevenday old potted wheat plants. The compounds were prepared for testing as follows:

(a) Example 2.One-half gram of 1-(4-chlorophenyl)-3-carboxy-4,6-dimethylpyrid-2-one was dissolved in ml. of acetone.

(b) Example 30.One-half gram of l-(4-chlorophenyl)-3-carboxy-4,6-dimethylpyrid-2-one (1.8 millimoles) was dissolved in 18 ml. of 0.1 N sodium hydroxide and TABLE IX.INHIBITION OF WHEAT PLANTS BY FOLIAR APPLICATION Percent inhibition at- 0.5 1 2 lbs./a.

In seed treatment tests an aqueous solution or suspension of the test compound was prepared and diluted to various percent concentrations. Seeds were then immersed in these preparations for about 20 hours, after which they were washed with Water, planted in untreated soil, and the germination and growth subsequently observed.

In one such greenhouse test the sodium salt of 1-(4- chlorophenyl)-3-carboxy-4,6-dimethylpyrid-2-one (Example 30) was dissolved in water to give a series of concentrations varying from 0.03% to 3%. Seeds of barley, oats and wheat were treated with these solutions as indicated above and planted. Four weeks after planting the percent inhibition was determined. A 100% inhibition 19 indicates that the seeds did not germinate or that no plants appeared. Table X gives the results:

TABLE X.INHIBITION OF CEREALS BY SEED TREATMENT Percent inhibition at percent concenion- Plant specie 0. 03 0. 1 0. 3 1 3 20 the preferred range is from 0.05 to pounds per acre. Seeds may be treated with the compounds themselves or with any concentration of a solution or formulation of them.

The compounds of this invention may be employed as plant growth response agents either individually or as a mixture of two or more of them. They also may be used in combination with other plant growth regulatory compounds such as maleic hydrazide, succinic acid 2,2-dimethylhydrazide, choline and its salts, (Z-chloroethyl) trimethylammonium chloride, triiodobenzoic acid, tributyl-2,4 dichlorobenzylphosphonium chloride, polymeric N-vinyl-2-oxazolidinones, tri(dimethylaminoethyl) phosphate and its salts, and N-dimethylamino-l,2,3,6-tetrahydrophthalamic acid and its salts. The compounds of this invention may also be combined with a herbicide for use on plants which are not sensitive to the heribicide at weed controlling rates. For example, they may be combined with 2,4-D for use on monocotyledonous plants such as cereals and turf grasses, with 3',4'-dichloropro- TABLE XI.-TYPICAL PLANT RESPONSES OBTAINED WITH EXAMPLE 1 Dosage range Plant species Response observed (lbs./a.)

Apple (seedlings) (Malus sylvestris) gggm (high dosag af pinasty 1-20 m B le Hordeum vul are Seed (higher dosages)- 075.3

at y g Initiation of flowering delayed (higher dosages). Bamwdgmss (Echinochlw "Walla --{S2231ll fff flYjji:1:1:13;:::::::::::::::::::::: .313: HO Beans (dwarf) (Phaseolus vulqaris) se eiglfl i g l er dosages), number of bean pods increased, malforma- 346- aves. gocklzegur (Xon)thium pensylvanicum) g tkem h igltiltdosage), malformation of burs 0 orn ea mazze cm 5 1g y Cotton (Gaasg/pium herbaceum). Stem (higher dosages) 0. 5-3 Cucumber (Oucumis stivus).-.. Seed, cucumber fruit increased in number 0. 5-4 Egg lant (Solanummelongena) Pl ant s gransplanted 2 weeks before treatment were dead or re- 0.5-4

Flax (Linum'usit tissium) g gi g g 0. 54 Grape (seedlings) (Vitis vinifera) Stern, leaf epinasty (high dosage) 2-20 Mimosa (seedlings) (Acacia armata) Stem 1 g Nutgrass (Cyperus esculentus)..." $0111 y) 5 em Oats (Avena satiua) d (higher dosages)- 0. 75-3 Number and weight of h Peach (seedlings) (Prtmus peraica)" item (shghtly) i 1-8 Pm Pi weed (Amaranthus retro/iezus) ie ed t( l lig h e r c l osa gesd .d 1-10 ng o 0 er ea s gice (gryzla eating); gtem, broader leaves 0022-? e am e cerea e em y {Seed (higher dosages)- Safilower (Carthamus tinctorius) s eiiziiihfiua ee g er osages Stem (slightly) S y y (higher dosages) 0. 5-4 Squash (Curcurbita pepo) Seed (higher dosages), number of squash fruit increased. 0. 5-4 Sugar beets (Beta vulgaris) Decreased foliage weight and increased beet weight 0.5-8 Tomato (Lycoperaicum esculentum) Flowering prolonged, fruit setting and development delayed. 0. 5-4 Turf grass St 1-10 om Seed (higher dosages) Wheat (Tmwum vulva) "{Pl ants had shorter, thicker stems and shorter, broader and thicker i 20 eaves.

N0'rE.Stem=Stem elongation inhibited; Seed=Seed formation inhibited.

In similar tests, by foliar application, no appreciable growth inhibition was observed on carrot (Daucus carota), chrysanthemum (Chrysanthemum spp.), radish (Rap/mulls sativus), sunflower (Helianthus mums) and turnip (Brassica rapa).

When the compounds of this invention are applied to plants or to the habitat of plants, they give a growth regulating response in the dosage range of about 0.01 to 30 pounds per acre (0.011 to 33 kilos per hectare). At the higher dosages, herbicidal responses may be manifested. Depending on the type of response desired the amount will vary with the plant species to be treated. Generally may be anionic, cationic or non-ionic. For the water- 21 22 soluble salts cationic and non-ionic surfactants are pre- The effect of the compounds of this invention on the ferred. Commonly used surfactants are well-known in the reproductive parts of corn plants was explored with the art and may be found in John W. McCutcheons publicasodium salt of 1-(4-chlorophenyl) 3 carboxy 4,6 dition: Detergents and Emulsifiers, 1967 Annual, John W. methylpyrid-Z-one (Example 30). For this test, a 65 day- McCutcheon Inc., Morristown, NJ. 5 maturing, dwarf variety of corn (Zea mays var. Golden The compounds of this invention may be formulated Midget) was used. For each treatment, five seeds in various ways as for example emulsifiable concentrates, were planted in a pot of soil. Five replications were used.

Wettable powders, dusts, granules and pellets. Usually for Three weeks after seeding, each pot was thinned to two application to the plant or plant parts or the plant habitat, plants per pot and treated with a soil drench application the formulations are extended with a suitable carrier. of the test compound on a weekly basis for three weeks. Emulsifiable concentrates are most usually extended with Each dosage applied amounted to 0.25, 1, 4 and 8 lbs./A.

a liquid carrier such as water and dusts; granules and Observations were made 7 weeks after planting. The folpellets are most usually extended with a solid carrier such lowing Table XII gives the observed effect on plant size, as mineral clays. anther and silk development and tassel morphology as Emulsifiable concentrates may be made by dissolving compared to untreated control.

TABLE XII.--EFFEOT ON GROWTH AND FLOWERING OF CORN Length of Development of- Plant third interheight node from Tassel (cm.) tassel (cm.) Injury Anther Silk branching NorE.-N=normal; Sl=slight reduction; Mod=moderate reduction; Sev=severe reduction; St=stimulation.

the compounds in an organic solvent and adding one or The anther, the polliniferous part of a stamen, was sigmore solvent-soluble emulsifying agents. Suitable solvents nificantly affected whereas the silk was not. The silk could are usually water-immiscible and may be found in the be readily pollinated and ear size and development were hydrocarbon, chlorinated hydrocarbon, ketone, ester, alfound to be normal. There is a definite indication that cohol and amide classes of organic solvents. chemical hybridization of corn could be achieved.

Wettable powders may be made by incorporating the In certain instances it is desirable to produce sturdy compounds in an inert, finely divided solid carrier along plants, e.g. to prevent lodging or where machine transwith a surfactant which may be one or more emulsifying, planting of seedlings is practiced. One such instance is in wetting, dispersing or spreading agents or blends of these. n'ce culture. Suitable carriers may be found in the classes of clays, Tests were conducted in rice paddy flood pans simulatsilicates, silicas, limes, carbonates and organic carriers. 40 ing conditions used in paddy type culture. Pots of 14 Solid compositions in the form of dusts may be made days rice plants were used in this study. At the time of by compounding the compounds of this invention with treatment, these plants were determined to have an averinert carriers conventionally employed for the manufacage height of 13 cm. and were in the 2-early 3-leaf stage ture of pesticidal dusts for agricultural use, such as tales, of development. finely particled clays, pyrophyllite, diatomaceous earth, Following installation of the test plants, flood water magnesium carbonate or wood or walnut shell flours. d pth was adjusted to 3 inches (7.6 cm.) above the soil Granular or pelletized formulations may be made by Surface. Water temperature was maintained at a minimum incorporating the compounds into granular or pelletized f 75-80 F. during the course of the study. Flood water forms of agronomically acceptable carriers such as granu- Was drained (and saved for subsequent reflooding) 48 lar clays, vermiculite, charcoal, ground corncobs or bran. hours before observations were made.

Representative compounds of this invention have 50 Treatments were applied by weighing the treatment shown fungicidal activity. For extmple, the compound of equiv-111ent (111/ amount of compound, dissolving the Example 2 has given control of bean powdery mildew materials in a solvent (preferably water or acetone), and (Erisiphe polygtoni) and the compounds of Examples 5, 10 mixing thlS resultant SOllllZlOll With the fiOOd water. The and 25 have given good ,control of tomato late blight treated paddy was allowed to remain in a quiescent state (Phytophthora infestans) until draining just prior to evaluation.

The growth regulatory action of the compounds of the Observations were first made 14 days after treatment. present invention may be advantageously employed in When visual observations were made, a scale of 0 (no various ways. The production of shorter and thicker stems inhibition) to 10 (complete inhibition) was used as the in Cereal grains reduces the tendency toward lodging- T rating index. Comparisons of treated plants to untreated grasses may be maintained at 10W height and the neces control plants were made to determine departures of slty for imquent mowmg anewated' The plant growth on the treated plants from normal growth. For some of the embankment? Such as roadsides p i f to treatments, plant height measurements were made after l and at i i 2168' the visual observations and then again after 28 days. that: value ere may e an a vantage m Pro ucmg 5 Tabel XIII contains the visual observation data and dormant period in certain plants. The control of flowering and fruiting may be advantageous in the production figl g i gfi gz i g b gi g of seedless fruit and for hybridization. Delaying the vege- 1 1 Ion Va ues We e tative process or altering the time of flowering and fruiting may result in more advantageous harvest dates or increased flower, fruit and/or seed production. The Percent inhibition=100 chemical pruning of trees, shrubs, ornamentals and nur- Height of Height of control at sery stock may be beneficial. Other applications of the treated plants-treatment time compounds of the present invention will suggest them- 100 of Height of control at 121m; eto those skilled 1n the art of agriculture and horticontrol p ants treatment time TABLE XIIL-RIOE PLANTS TREATED THROUGH PADDY FLO O D WAT E R Visual Plant height Percent rating (cm.) inhibition index Lbs./a. (2 wks.) 2 wks. 4 wks. 2 wks. 4 wks.

Treatment with Example:

l 2(a) =1-(4-chlorophenyl) -3-cyano-4,6-dimcthylpryid-2-one N era-Control at treatment time=13 cm.

The reduction in plant height is quite striking. The resulting plants are much sturdier, they will not lodge easily and they are much more adaptable to handling such as for transplanting. It was also noted that there were no visible manifestations of injury to the treated rice plants. It was also noted that tillering was initiated earlier in the treated plants as compared to the controls.

A test was run to study the gametocidal activity of the compound of Example on barely. For this test, the compound was applied as an aqueous solution to barley (Hordeum vulgare var. Dickson) in five different stages of growth from young seedlings up to and including the boot stage of development. Plants were sprayed to run-off with dosage rates of 0.25, 1, 2, 4 and 8 lbs. per 100 gal. When the barley plants reached the flowering stage of development, each spike or seed head was covered with a paper bag to prevent cross pollination. In those instances where the treatments delayed flowering, the spikes were not covered with paper bags because viable pollen from the nonsprayed checks would no longer be available at these later dates. The most positive results were obtained with the plants in the boot stage. These results are given in Table XIV.

TABLE XIV.-GAl\IETOCIDAL ACTIVITY ON BARLEY Seed present 1 Eighty-eight days after treatment.

It will be noted that no seed was produced in those spikes which were covered to prevent cross pollination. This absence of seeds indicates that fertilization had not taken place and that male sterility had been induced with the topical applications of the sodium salt of 1-(4-chlorophenyl 3 carboxy 4,6 dimethylpyrid 2 one. The presence of seed in a few treated seed heads that were not covered would further indicate that cross pollination had occurred and the treatment had not affected the female portion of the spikelet, particularly the 0.25 and 1 lb. dosage. The higher dosage rates delayed the time of flowering; thus, no pollen was available at this time for cross pollination since the non-treated check plants had flowered at an earlier date.

A representative compound of this invention has been found to be a ripening agent for sugarcane (Saccharum ofiicinarum). In one such test, the compound of Example 30 was applied as an aqueous solution at a dosage of about 3 lbs/acre of the active material to the sugarcane foliage approximately one month prior to harvest. For comparative purposes, plants treated with an art recognized ripening agent (dimethylammonium trichlorobenzoate sold under the trademarked name of Trysben) and untreated plants were used. At four weeks (first harvest) and five weeks (second harvest) after application, the cane was harvested, juice extracted and the juice examined for sugar content. Table XV gives the results with the percent cane sugar expressed as percent pol and the percent purity" expressing the percent sugar in the solids.

TABLE XV.-SUGARCANE RIPENING SCREENING TEST As judged by the amount of sugar in the juice and the purity as compared to the untreated control, the sodium salt of 1-(4-chlorophenyl) 3 carboxy 4,6 dimethylpyrid-Z-one is an excellent ripening agent for sugarcane.

Field tests were run which demonstrated that the yield of soybeans could be increased by application of representative compounds of this invention. In one such test, an aqueous solution of the compound of Example 30 was applied to soybeans at the prebloom stage, at a rate of approximately 1 bl./A. Yield increases amounting to 9- 19% were obtained.

What is claimed is:

1. A method of inhibiting plant growth which consists of applying to a plant, to plant seeds or other plant parts or to the habitat of a plant an effective amount of a compound of the formula a R5mCY Ra N O ziryl wherein R and R are methyl or ethyl,

R is hydrogen, methyl, ethyl or chlorine,

Y is selected from the group consisting of Br, Cl, NH and OR wherein R is chosen from the group consisting of hydrogen, alkyl groups of 1 to 5 carbon atoms and a physiologically acceptable salt-forming cation which converts the compound into a water-soluble salt, and

aryl is selected from the group consisting of I I G n I X X wherein X is selected from the group consisting of fluoro, chloro,

bromo, iodo, methyl, trifluoromethyl and methoxy, nisO, l orZand X is selected from the group consisting of amino, fluoro, chloro, bromo, iodo, alkyl of 1 to 5 carbon atoms, trifluoromethyl, methoxy and nitro, except that it may also be hydrogen when n is 1 or 2 and X is at least one halogen in the 3-position. 2. A method according to claim 1 wherein the growthinhibiting amount of the compound is in the range of 0.01 to 30 pounds per acre.

3. A method according to claim 1 wherein the growthinhibiting amount of the compound is in the range of 0.05 to 15 pounds per acre.

4. A method according to claim 1 in which the application of said compound is made to the plant foliage or to the soil in which the plant is growing.

5. A method according to claim 1 in which the application of said compound is made to plant seeds.

6. A method according to claim 1 in which the compound is 1 (4 chlorophenyl)-3-carboXy-4,6-dimcthylpyrid-2-one or one of its salts.

7. A method according to claim 1 in which the compound is 1 (3,4 dichlorophenyl) 3 carb0xy-4,6- dimethylpyrid-Z-one or one of its salts.

8. A method according to claim 11 in which the compound is l-(4-chloronaphthyl) 3-carboxy-4,6-dimethylpyrid-Z-one or one of its salts.

9. A method according to claim 1 in which the compound is applied to a cereal crop, or to the seed to be planted to produce such a crop, to inhibit growth and thereby to decrease the lodging tendency.

10. A method according to claim 9 wherein said plant 1s rice.

11. A method according to claim 10 in which the compound is applied to turf grasses, or to the seed to be planted to produce a turf, to control the height of the turf.

12. A method according to claim 10 in which the compound is applied to a crop of oats or to the seeds to be planted to produce such a crop, to increase the number of fruit.

13. A method according to claim 1 in which the compound is applied to a crop of beans, or to the seeds to be planted to produce such a crop, to increase the number of fruit.

14. A method according to claim 1 in which the compound is applied to a crop of curcurbits, or to the seeds to be planted to produce such a crop, to increase the number of fruit.

References Cited UNITED STATES PATENTS 3,355,278 11/1967 Weil et a1 7l94 3,535,328 10/1970 Zielinski 7l94 FOREIGN PATENTS 970,968 9/1964 Great Britain 7l94 1,031,264 6/1966 Great Britain 7l94 LEWIS GOTTS, Primary Examiner G. HOLLRAH, Assistant Examiner I UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,76l,2 +O Dated Sejgtember 25, 197.3

Michael C. Seidel, Kenneth L. Viste and Inventor(s) ROY Y. Yih

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the specification make the following changes:

Column 3, line #2, insert a comma after "3-carboxy- +,6-dimethylpyrid-2-one",

Column 3, line 56, "chlorine" Should read choline--,

Columns 11 and. l2, in the heading of Table 111,, the formula should read V CH v v 3 COOH CH3 a. N o

Columns 19 and ZO, in the heading for Table XI, "1" should read --2-.

Signed and sealed this 16th day of July' 197A.

(SEAL) Attest:

SON JR. c. MARS LL DANN i 'j t i ng C ficer Commissioner of Patents 

